Extraction by N,N-dimethylformamide with further column chromatography allowed obtaining concentrate of vanadylporphyrins from asphaltenes of heavy sulfurous oils with high vanadium content. The prevailing types of vanadylporphyrins, their ratio, and molecular mass distribution were determined. The influence of obtained vanadylporphyrin concentrates on the stability of asphaltenes in the system “solvent/precipitator” was investigated. Kinetic studies using UV–vis spectroscopy have revealed that an increase in the content of vanadylporphyrins in asphaltenes leads to acceleration of their deposition from solution and destabilization of colloidal systems.

中文翻译：

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钒基卟啉在高钒重油的沥青絮凝和沉淀中的作用

用进一步的柱色谱法通过N，N-二甲基甲酰胺萃取可以从具有高钒含量的重质亚硫油的沥青质中获得钒基卟啉的浓缩物。确定了钒氧卟啉的主要类型，它们的比例和分子量分布。研究了在“溶剂/沉淀剂”体系中获得的钒氧卟啉浓缩物对沥青质稳定性的影响。使用紫外-可见光谱的动力学研究表明，沥青质中钒基卟啉含量的增加会导致其从溶液中的沉积加速，并使胶体系统不稳定。